The present invention relates to an on-vehicle navigation apparatus, a turnoff road guiding method, a driving lane-specifying device, and a driving lane specifying method.
An on-vehicle navigation apparatus, disclosed in Japanese Patent No. 3161280, is configured such that in order to enhance a safety of in driving during a lane change, a current location, inclusive of a driving lane, of an own vehicle is specified based on road information acquired from a Differential Positioning System (D-GPS) serving as a satellite positioning sensor, a vehicle speed sensor, a direction sensor and road map data stored in a map information database.
Such an apparatus is operative to receive correction data through FM broadcasting based on a positioning error calculated in a D-GPS standard station that receives radio waves from a GPS satellite.